Annual report pursuant to Section 13 and 15(d)

Debt - Future Principal Payments on Debt (Details)

v3.3.1.900
Debt - Future Principal Payments on Debt (Details) - USD ($)
$ in Thousands
Dec. 31, 2015
Dec. 31, 2014
Line of Credit Facility [Line Items]    
Total debt, net carrying amount $ 16,957 $ 22,131
Convertible Notes Payable [Member]    
Line of Credit Facility [Line Items]    
2016 8,429  
2017 8,567  
2018 818  
Total debt, net carrying amount 17,814  
Hercules Term Loan [Member]    
Line of Credit Facility [Line Items]    
Total debt, net carrying amount 16,194 $ 19,070
Hercules Term Loan [Member] | Convertible Notes Payable [Member]    
Line of Credit Facility [Line Items]    
2016 7,666  
2017 8,567  
2018 818  
Total debt, net carrying amount 17,051  
Magna August Note [Member]    
Line of Credit Facility [Line Items]    
Total debt, net carrying amount 763
Magna August Note [Member] | Convertible Notes Payable [Member]    
Line of Credit Facility [Line Items]    
2016 $ 763  
2017  
2018  
Total debt, net carrying amount $ 763